# CVE-2024-34363: Envoy can crash due to uncaught nlohmann JSON exception

Status: published. Published: 2024-06-04. Updated: 2026-11-05.

Envoy is a cloud-native, open source edge and service proxy. Due to how Envoy invoked the nlohmann JSON library, the library could throw an uncaught exception from downstream data if incomplete UTF-8 strings were serialized. The uncaught exception would cause Envoy to crash.

## Remediation

No remediation reported in collected sources

## Affected products and versions

- envoyproxy / envoy: >= 1.30.0, <= 1.30.1 (affected); >= 1.29.0, <= 1.29.4 (affected); >= 1.28.0, <= 1.28.3 (affected). Source: CNA: GitHub_M

## NVD configuration conditions

Affected CPE matches depend on the following AND/OR and negation conditions:

```json
[
  {
    "negate": false,
    "nodes": [
      {
        "cpeMatch": [
          {
            "criteria": "cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:*",
            "versionEndExcluding": "1.28.4",
            "versionStartIncluding": "1.28.0",
            "vulnerable": true
          },
          {
            "criteria": "cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:*",
            "versionEndExcluding": "1.29.5",
            "versionStartIncluding": "1.29.0",
            "vulnerable": true
          },
          {
            "criteria": "cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:*",
            "versionEndExcluding": "1.30.2",
            "versionStartIncluding": "1.30.0",
            "vulnerable": true
          }
        ],
        "negate": false,
        "operator": "OR"
      }
    ],
    "operator": "OR"
  }
]
```

## Severity and prioritization

- CVSS 3.1: 7.5 (high); CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H; source: CNA: GitHub_M

- CVSS 3.1: 7.5 (high); CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H; source: NVD: nvd@nist.gov

- CVSS 3.1: 7.5 (high); CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H; source: NVD: security-advisories@github.com

- CISA KEV: No listing in collected sources

- EPSS: 0.67% as of 2026-11-05; percentile 52.30%

- SSVC: exploitation none; automatable no; technical impact partial; source ADP: CISA-ADP

- Weaknesses: CWE-248

## Exploit evidence

- exploit: https://github.com/envoyproxy/envoy/security/advisories/GHSA-g979-ph9j-5gg4 (security-advisories@github.com)
- exploit: https://github.com/envoyproxy/envoy/security/advisories/GHSA-g979-ph9j-5gg4 (af854a3a-2127-422b-91ae-364da2661108)

## References

- https://github.com/envoyproxy/envoy/security/advisories/GHSA-g979-ph9j-5gg4 (CNA: GitHub_M; x_refsource_CONFIRM)

- https://github.com/envoyproxy/envoy/security/advisories/GHSA-g979-ph9j-5gg4 (ADP: CVE; x_refsource_CONFIRM, x_transferred)

- https://github.com/envoyproxy/envoy/security/advisories/GHSA-g979-ph9j-5gg4 (security-advisories@github.com; Exploit, Third Party Advisory)

- https://github.com/envoyproxy/envoy/security/advisories/GHSA-g979-ph9j-5gg4 (af854a3a-2127-422b-91ae-364da2661108; Exploit, Third Party Advisory)

## Provenance

- CNA: GitHub_M: https://www.cve.org/CVERecord?id=CVE-2024-34363; retrieved 2026-11-05; source updated 2026-11-05

- NVD: https://nvd.nist.gov/vuln/detail/CVE-2024-34363; retrieved 2026-11-05; source updated 2026-11-05

- FIRST EPSS: https://api.first.org/data/v1/epss?cve=CVE-2024-34363; retrieved 2026-11-05; source updated Not reported

Revision: 0081f863eb54d46b51f2d626a694cb82a5723ee95a0a2a08c331076a50ff4de2

Canonical: https://y2.dev/cve/CVE-2024-34363

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